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MFFERS. PKOTO-LITHOGRAFKER. WASHINGTON. D. C.

11W. EVANS, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO HIMSELE ANDO. O..'IhlNgIQfN,S,`

OF SAME PLACE,`

EQUALIZNG THE AGTIONWGF SPRINGS-IN1 GOVERNGBIS.

Specification of Letters-Eatent No.` 33,123; dated August-20,1861.

To all whom it may concern:

Be it known that LTIAMPTON lV. EVANS, of Philadelphia, Pennsylvania,have invented a new and improved Mode of Equalizing the Action ofSprings in Governors; and l do hereby declare the following to be afull, clear, and exact description of the same, reference being had tothe accompanying drawings and to the letters of reference markedthereon.

My invention consists in combining a spring with a governor spindle androds so arranged as to form a knee joint substantially in the mannerdescribed hereafter so that the force applied to overcome the rigidityof the spring may be transmitted through a leverage constantlyincreasing as the resistance of the spring increases thereby eqiralizingthe action of the said spring, a desirable object to be obtained undercertain circumstances described hereafter.

In order to enable others to make and use my invention I will nowproceed to describe the manner in which it may be constructed andapplied.

On reference to the accompanying draw- Figures l and 2 illustrate myinvention as applied to a governor for steam engines; Fig. 3 a sectionalview of parts of Figs. l and 2.

On reference to Figs. l, 2 and 3, A represents the spindle of thegovernor and B and B the weighted arms hung tothe top of the spindle inthe usual manner. To the weights n ct of the arms B and B are jointedthe upper ends of the rods C and C the lower ends of the latter beingconnected to the sleeve D which is fitted snugly to, but arranged toslide freely on the spindle A.

E is a spring connected at a point midway between its opposite ends tothe spindle A by means of nuts t and c, which are adapted to the screwedportion of the said spindle.

To one end of the spring' is jointed a rod F and to the opposite end asimilar rod F, each rod being connected to a coupling Gr by means of anut Z one of these couplings being connected to a lug on one side andthe other to a` lug on the opposite side of the upper end of the sleeveD. The lower end of the latter has a recess [L for receiving the end oithe usual governor lever through which the movement of the sleeve iscommunicated to the throttle valve of the steam mg which forms a part ofthis specification` On reference to F ig. l the sleeve D is lillustrated as depressed to the limit of its downward movement asregulated by this nut. As the governor revolves the weighted arms williiy out and the sleeve will rise to an extent regulated by the speed ofthe governor and the rigidity of the spring E. Now supposing this springacted directly on the sleeve without the intervention of the rods F andF', it will be evident that the higher the sleeve rises through thecentrifugal 'orce of the weights the greater will be the opposing forcepresented by the increased rigidity of the spring as the opposite endsof the latter are raised, consequently the governor will be irregular inits movement the irregularity being in proportion to the dilierence inthe rigidity of the spring as the ends of the latter are raised. Byconnecting the spring to the sleeve by means of the rods F and F howeverthe case is diiierent, as they forni with the sleeve and spring the wellknown knee joint, so that as the sleeve is raised it acts on the springthrough 'a constant leverage gradually increasing as the sleeve risesand as the rigidity of the spring increases. Thus in Fig. l where thesleeve is depressed to the limit of its downward movement, the forceapplied by the revolving balls tending to raise the ends of the springwill `be applied through a leverage equivalent to that represented bythe blue lines y and y the former representing the long arm of the leveracted upon by the sleeve and the latter the short arm acting on thespring and the point g being the fulcrum of the lever. As the sleeverises the long arm of the lever becomes gradually longer and the shortarm shorter so that by the time the sleeve has arrived at the positionshown 1n F ig. 2, the leverage on the spring will have` been increasedto the proportion represented by the blue lines in that figure.

t will be evident without further description that by transmitting theforce imparted to the sleeve by the action of the revolving Weights tothe spring E through the medium of a knee joint the increasing rigidityof the spring as its opposite ends are raised is counteracted by anincreased force applied to raise the said ends and consequently that theaction of governor is uniform throughout.

I claim as my invention and desire to secure by Letters Patent-Combining a spring With the governor spindle A and rods F and F soarranged as to form a knee joint substantially as and for the purposeherein set forth. In testimony whereof, I have signed my name to thisspeciiication7 in the presence of 15,

tvvo subscribing Witnesses.

HAMPTON W. EvANs.l Y

Vitnesses AHENRY HovvsoN,l

CHARLES HoWsoN.

